The invention relates generally to electrical terminal connectors, and more specifically to terminal connectors adapted to provide multi-battery couplings for batteries that utilize tab type terminals.
As more and more segments of the business environment enter the information age, more and more computers and computing power are required. As businesses move from the old to the new economy, their reliance on the processing, transference, and storage of digital information is becoming a more and more critical aspect of their overall business strategy. While in the past, computer crashes were seen as a mere nuisance, the loss of computing power and business data may well devastate a business""s ability to survive in this new economy. As such, the need for reliable, uninterruptible electric power to maintain the operational status of the computing equipment and the integrity of the digital data continues to rise.
To meet these requirements, uninterruptible power supplies (UPS) have been developed that utilize a bank of electric storage batteries and solid-state conversion equipment to provide continuous electric power to a business""s computer systems in the event of a loss of power from the utility. The number of batteries contained within an UPS is dependent upon the business""s length of time that it needs to operate in the event of a utility power system failure. However, with many utilities requiring rolling brownouts during peak electric usage periods, the number of batteries being utilized continues to increase.
A typical UPS includes multiple banks of series connected batteries that supply DC electric power to a solid state power inverter. The inverter converts the direct current battery power to alternating current power for use by computing utilization equipment. As illustrated in FIG. 15, a typical battery configuration includes two tab type output connectors 200, 202 from which their DC power is supplied. The batteries 204a-n are placed side-by-side to form a battery bank for the UPS. The series coupling between each of the individual batteries in the bank is accomplished by providing a series coupling device 206. This device 206, as illustrated in greater detail in FIG. 16, consists of a simple assembly of two tab type connectors 208, 210 that are crimped to the ends of a jumper wire 212. While this simple apparatus 206 provides adequate series connections between each of the batteries in the battery bank, it suffers from a number of disadvantages.
Specifically, while the material costs of the apparatus 206 are fairly low, its construction and installation labor requirements are quite high. First, after the jumper wire 212 has been cut to the proper length, the insulation on each end must be removed to allow for proper electrical connection with the tab connectors 208, 210. The bare wire 214 must then be inserted into the crimping end 216 of the tab connector 208, 210 and crimped. The crimping must be controlled to supply the electrical connection to the wire 212, and to mechanically secure the bare wire 214 therein. This operation typically requires a special crimping tool to insure that the crimp is sufficient to meet industry standards for the pull requirement for this connection. Once this operation has been performed for each end of the jumper wire 212, the apparatus 206 must be installed to complete the series coupling of the batteries in the battery bank.
The installation of the apparatus 206 presents the second problem area for this configuration, that being the labor intensity required. Specifically, the tab connectors 208, 210 typically provide a friction or interference fit on the battery tab connectors 200, 202. As such, they can be fairly difficult to install, requiring that the assembly personnel grip one of the connectors 208 and force it onto one of the terminals 202. This process is often aided by a wiggling type motion of the connector 208 while pushing it on the battery""s tab connector 202. While this wiggling type movement does not present a significant problem for the installation of the first of the two connectors of apparatus 206, a similar motion during the installation of the second such connector may fatigue the wire 214 at the junction with the crimping end 216 at one or both of these junctions. This results from the fact that one of the connectors is already fixed on a battery terminal while the other end is being manipulated in a wiggle fashion.
Further, once installed, these jumpers 206 present loops of wire that may be easily caught on the chassis, by monitoring equipment, maintenance personnel, etc. during installation, operation, or maintenance of the UPS. If such were to occur, once again the crimped couplings of the wire 214 to the connector crimp end 216 would be stressed. Eventually, such continued stressing and fatigue could lead to a failure of the jumper wire connection 206. Even if the jumper 206 did not actually break, it is possible that equipment catching the wire loop of this jumper 206 could dislodge one or both of the connections to the battery""s tab terminals.
In addition to these problems, the installation of these jumpers 206 may also be uncomfortable for the assembly personnel who must literally install hundreds of such connections in a day. While the assembly personnel may wear gloves to protect his or her fingers from developing calluses, or may use an insertion tool such as a pair of needlenose or other type pliers, each of these personnel aids have their own drawbacks. Specifically, gloves may make it harder to grip the small connectors 208, 210, and may also reduce the assembler""s ability to feel when the coupling is fully seated. This may result possibly in bending the tab connectors 200, 202 on the battery. Likewise, the use of pliers or other like tools to grip the connectors 208, 210 during the insertion onto connectors 200, 202 may result in damage to or even breakage of the connectors 200, 202. As may well be appreciated, once the connector 200, 202 is broken off of a battery, that battery cannot be used unless or until it can be repaired. Further, the use of pliers or other like tools may flatten or otherwise damage the connection surfaces on the connectors 208, 210. This would inhibit or diminish the connector""s ability to maintain both electrical and mechanical contact on the battery""s tab connectors 200, 202.
Therefore, there exists a need in the art to provide a simple, reliable, and cost effective apparatus to provide the series coupling between adjacent batteries in a UPS which overcomes these and other known problems existing in the art.
It is a feature of the battery terminal jumper clip of the invention to provide a single piece, unitary construction capable of electrically coupling adjacent batteries having tab type electrical terminals thereon. It is a further feature that the battery terminal jumper clip provides a snap-on, locking mechanism to inhibit the removal of the clip once installed on adjacent batteries in a battery bank. Further, it is a feature of the battery terminal jumper clip to provide a guided insertion surface to ease the installation of the clip on adjacent batteries during the battery bank manufacturing process. Additionally, the battery terminal jumper clip also includes axially retention surfaces to prevent the battery terminal jumper clip from working off the tab connectors from one side or another while still allowing limited axially movement of the connector due to shifting of the equipment or other causes of battery movement.
It is also a feature of the battery terminal jumper clips to provide a solid conductive bus for the conduction of current between adjacently mounted batteries in a battery bank. Preferably, the bus provided by the battery terminal jumper clip maintains a flat profile that is not prone to catching on other equipment, like the prior use of a loop of wire to provide this coupling. Additionally, it is a feature of the battery terminal jumper clips to provide a tab retention clips. These clips provide both electrical and mechanical coupling to the tab terminals of each of the two adjacent batteries to which the clip is attached. Preferably, an independently moveable retention clip is included for each of the two tab type terminals for the two adjacent batteries. Alternatively, it is a feature of the battery jumper clips to provide bifurcated tab retention clips to allow for greater movement of the individual batteries within the battery bank, while still maintaining electrical and mechanical contact therewith. It is also a feature of the battery terminal jumper clips to provide an integrated auxiliary connection terminal to allow external monitoring equipment to monitor the battery voltage at the coupling or to allow the supplying of power therefrom. This auxiliary connection terminal may preferably be integrated in to the top surface bus work, or may alternatively be provided as an integral portion of one of the axially retention surfaces.
Other features and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.